低温微滤技术制备富含β-酪蛋白和乳清蛋白的新型功能性乳蛋白配料

摘要

Commercial pasteurized skim milk was used as raw material,the pore size of membranes,temperatures,filtrate washing solutions and washing times on the effect of seperation and membrane flux were studied.SDSPAGE and HPLC were used as qualitative and quantitative analysis to accurately characterize proteins' separation.Results showed that at 4 ℃,using 30 nm ceramic membrane can obtain purified β-casein from skim milk,and with almost non-αs-casein.Besides,in order to maximize the separation of β-casein,deionized water was added to do the second level of filtration (or we called it as "diafiltration") for 4 times.The yields of the β-casein and whey protein were 51.7％ and 99.7％ respectively;β-casein was 51.1％ and whey protein was 40.0％ in the compound protein.The compound protein can be used in infant formula powder.%以市售的巴氏杀菌脱脂乳为原料,探究膜孔径、温度、洗滤液和洗滤次数等条件对β-酪蛋白和乳清蛋白分离效果和膜通量的影响,最终制备了富含β-酪蛋白与乳清蛋白的新型功能性乳蛋白配料.研究采用聚丙烯酰胺凝胶电泳和高效液相色谱对蛋白做定性和定量分析.研究表明,在4℃条件下,使用30 nm孔径的陶瓷膜,以水作为洗滤液,可使得β-酪蛋白的分离效果最佳;在最优条件下,脱脂乳经微滤浓缩3倍后,再在相同条件下补水洗滤4次,将膜过滤各阶段所得的透过液混合,可得到β-酪蛋白和乳清蛋白的产率分别为51.7％和99.7％,复合蛋白中β-酪蛋白和乳清蛋白所占比例分别为51.1％和40.0％,而αs-酪蛋白的含量得以大大降低,该功能性复合蛋白可作为一种新型的功能性蛋白配料用于配方乳粉等婴幼儿食品的研制.